Several new areas of development and application of the dynamic nmr (nuclear magnetic resonance) chemical exchange probe of the active site of enzymes will be explored. We hope to provide a novel experimental method for probing the structure of the transition state enzyme complex by studying the nmr spectra of transition state analogs as they reversibly bind to the enzyme. By also applying these techniques to substrate analogs, it should be possible to achieve a detailed understanding of the enzymatic mechanism of action. In addition an nmr chemical exchange method for the study of covalent substrate intermediates will be presented. This should provide answers as to whether a covalent intermediate does, in fact, exist and, most importantly, define the amino acid residue which covalently links to the substrate. These nmr techniques will be applied to the study of ribonuclease A, alpha-chymotrypsin, 3',5'-cyclic-AMP dependent protein kinase, phosphoglycerate mutase and nucleotide phosphotransferase. However, broad application of these ideas to other enzymes are anticipated as well. In addition, our recently proposed 31P chemical shift-torsional angle hypothesis will provide an important new probe of nucleic acids. We hope to study the conformational flexibility about the phosphate ester backbone of simple dinucleotides and oligonucleotides by 31P nmr spectroscopy. We plan to probe with this technique subtle polynucleic acid, drug, protein, and carcinogen interactions.